recording all the files in a large directory

Question

Hi,

I've got a number of directories with a large number of files in them (~10,000). I want to create a list of these files in my app, and have already threaded the io access so that the app doesn't freeze while they load. However if I exit the app before all files are loaded, the thread doesn't respond to the .Join() until the call to dirInfo.GetFiles(...) is completed:

// ... mythread
    DirectoryInfo dirInfo = new DirectoryInfo(path);
    foreach(FileINfo file in dirInfo.GetFiles(extension)) 
    {
        // with large directories, the GetFiles call above 
        //    can stall for a long time
        ...

Caching the files out of the foreach just moves the problem. I need some kind of threaded, callback-y way of finding the files in the directory and I'm not sure how to do that. Any help would be appreciated.

Many thanks, tenpn.

Answer 1

You should use a Thread from the ThreadPool class. This will make it a background thread and it should receive a ThreadInteruptException when the application closes.

Answer 2

You can call Thread.Abort() when your application is about to close (before the Join).

myThread.Abort();
// Wait for myThread to end.
myThread.Join();

Also, you might want to catch the ThreadAbortException in the thread method and do some finalization/cleaning, if necessary.

try {
    DirectoryInfo dirInfo = new DirectoryInfo(path);
    foreach(FileINfo file in dirInfo.GetFiles(extension)) 
    {
        // with large directories, the GetFiles call above 
        //    can stall for a long time
        ...
    }
}
catch (ThreadAbortException e)
{
    // cleaning
}